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排序方式: 共有1227条查询结果,搜索用时 15 毫秒
91.
92.
目的比较无创比例辅助通气(PAV)和压力支持通气(PSV)治疗慢性呼吸衰竭患者的疗效和依从性。方法20例稳定期慢性阻塞性肺疾病(COPD)呼吸衰竭患者随机选用PAV或PSV,记录患者动脉血气、平均潮气量(VT)、分钟通气量(VE)、气道峰压(PIP)和夜间通气时间;采用视觉模拟评分(VAS)评价通气舒适性、睡眠状况和不良反应。结果PAV和PSV治疗组VE和VT比较无显著差异(P均>0.05),PAV组PIP较低[(12.2±2.4)cm H2O比(15.6±3.8)cm H2O,P<0.05];PAV组夜间通气时间较长[(3.3±0.7)h比(2.6±0.5)h,P<0.05],口鼻咽干燥程度较轻[(3.6±0.7)分比(4.5±0.9)分,P<0.05],口腔漏气较少[(3.3±0.6)分比(4.4±0.8)分,P<0.01]。结论慢性呼吸衰竭患者无创PAV依从性较好。 相似文献
93.
目的 采用连续富集酶切一限制性片段长度多态性/聚合酶链反应(CED-RnP/PCR)探索K-ras基因在胰腺癌患者血浆中的表达。方法 以血浆代替以往的标本并采用CED-RFLP/PCR技术检测胰腺癌、非胰腺癌患者及健康对照者血浆K-ras基因突变情况。结果 胰腺癌患者血浆K-Fas基因的突变阳性率为73%,无假阳性率,高于胰液、十二指肠液的检测率,低于细针穿刺的检测率;胰腺良性病变患者及健康对照者血浆中未检测到K-ras基因的突变;胰腺癌组K-ras基因突变与非胰腺癌组及健康对照组相比具有显著性差别。结论 CED-RFLP/PCR法检测血浆K-ras基因突变技术具有简单、易行高效的特点,克服以往技术的弊端,对胰腺癌的诊断及鉴别有一定的应用价值。 相似文献
94.
目的 :HP悉尼菌株灌胃复制感染动物模型 ,观察康胃方对HP的根除及胃黏膜细胞保护作用。方法 :SD新生大鼠随机分为正常对照组、病理模型组、三联治疗组及康胃方组 ,除正常对照组外 ,每日经口接种 10 9CFU mlHP菌液 0 1ml,共 3次。 8周后进行UBT ,随即接受相应的治疗 ,共 4周。疗后第 4周 ,测定胃黏膜RO、NO、iNOS、MnSOD及NPSH的含量或活性。结果 :HP感染动物 ,UBT与胃黏膜所含RO、NO、iNOS和MnSOD明显升高 ,NPSH显著下降 (P <0 0 1)。康胃方治疗后 ,UBT降低 ,其他指标明显改善 (P <0 0 1)。结论 :康胃方对新生大鼠感染HP有明显的根除作用 ,并对胃黏膜有一定的细胞保护作用。 相似文献
95.
Yeh YP Luh DL Chang SH Suo J Chang HJ Chen TH 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2005,99(7):509-516
We aimed to assess whether tuberculin reactivity in adults is affected by bacille Calmette-Guerin (BCG) vaccination after 50 years of universal BCG vaccination with 80-95% coverage. A community-based study on tuberculin reactivity in 619 participants was conducted in February 2000 in Keelung city, Taiwan. Information on BCG vaccination policies and annual risk of infection (ARI) in the underlying population was extracted from consecutive national prevalence surveys relating to the period 1952-1997. Compared with the expected ARI estimate, the standardized morbidity ratio of positive tuberculin response for vaccination in infancy was 2.2 (95% CI 0.3-15.5) for those aged <10 years. The corresponding figures for older age groups ranged from 3.6 (95% CI 2.2-5.9) for those aged 10-12 years to 0.7 (95% CI 0.5-0.9) for those aged 57-67 years. This suggests that the effect of BCG vaccination on positive tuberculin response in adults aged >30 years is probably negligible irrespective of age at vaccination or revaccination and that the tuberculin skin test can be used to diagnose TB in control programmes in countries with moderate or high incidence of TB. 相似文献
96.
PURPOSE: The incidence of tuberculosis (TB) in Taiwan is known to be high in aboriginal mountain areas and low in the surrounding non-mountain areas. The aim of this study was to assess whether TB incident cases in the surroundings of mountain areas decreased with distance from foci of mountain areas. METHODS: The mountain areas in Taiwan are adjacent to each other and divided into four geographic groups. Townships with high TB incidence in each group were treated as the foci of TB infection. The surrounding townships were then classified, by distance away from foci, into three levels: < 20 km, 20 to 40 km, and 40 to 60 km. Data were obtained on a total of 84,366 TB cases from 1991 to 1997 from the Taiwan Tuberculous Disease Registry Center. RESULTS: The incidence of TB in each of the four groups was significantly higher in the mountain areas compared with non-mountain areas, with relative risks ranging from 8.4 (95% confidence interval [CI], 7.8-9.1) for the southern group to 15.0 (95% CI, 13.4-16.9) for the northern group. Relative risks for surrounding townships decreased with distance in all four groups. Such a gradient relationship was statistically significant. CONCLUSIONS: A significant dose-response relationship between distance from townships with a high incidence of TB and the incidence of TB in the surrounding areas has been demonstrated. 相似文献
97.
Qi X Wang X Wang L Wang Q Cheng S Suo J Chang J 《European journal of medicinal chemistry》2005,40(8):805-810
Since the discovery of 2,2'-dimethoxycarbonyl-4,4-dimethoxy-5,6,5',6'-biomethylenedioxy-biphenyl (DDB) as a potent anti-HBV agent, we have studied the structure-activity relationships of 4,4'-dimethoxy-5,6,5',6'-dimethenedioxy-2-alkyloxycarbonyl-2'-(4-substituted benzyl piperazin-1-yl)carbonyl-biphenyl as anti-HBV agents. Therefore, it is rational to extend this study to the 3,3'-disustituted-4,4'-dimethoxy-5,6,5',6'-dimethenedioxy-2-alkyloxycarbonyl-2'-Serine derivatives. Thus, in an attempt to develop an efficient method for the preparation of a large number of DDB derivatives, the reaction between a DDB acid chloride and serine derivatives on solid support was studied. The structure of resulted compounds was confirmed by LC-MS and (1)H NMR analysis. Compounds 2a, 2d, 2f, 2j showed in vitro anti-HBV activity without significant toxicity up to 100 microM. 相似文献
98.
Citron BA Zoloty JE Suo Z Festoff BW 《Brain research. Molecular brain research》2005,135(1-2):122-133
Tissue transglutaminase (tTG) is a member of a multigene family principally involved in catalyzing the formation of protein cross-links. Unlike other members of the transglutaminase family, tTG is multifunctional since it also serves as a guanosine triphosphate (GTP) binding protein (Galpha(h)) and participates in cell adhesion. Different isoforms of tTG can be produced by proteolysis or alternative splicing. We find that tTG mRNA is expressed at low levels in the mouse CNS relative to other tissues, and at lower levels in the CNS of mouse in comparison to that of human or rat. tTG mRNA levels are higher in the heart compared to the CNS, for example, and much higher in the liver. Within the CNS, tTG message is lowest in the adult cerebellum and thalamus and highest in the frontal cortex and striatum. In the hippocampus, tTG expression is highest during embryonic development and falls off dramatically after 1 week of life. We did not find alternative splicing of the mouse tTG. At the protein level, the predominant isoform is approximately 62 kDa. In summary, tTG, an important factor in neuronal survival, is expressed at low levels in the mouse CNS and, unlike rat and human tTG, does not appear to be regulated by alternative splicing. These findings have implications for analyses of rodent tTG expression in human neurodegenerative and neurotrauma models where alternative processing may be an attractive pathogenetic mechanism. They further impact on drug discovery paradigms, where modulation of activity may have therapeutic value. 相似文献
99.
Suo Z Risberg B Karlsson MG Villman K Skovlund E Nesland JM 《International journal of surgical pathology》2002,10(2):91-99
Expression of EGF, HB-EGF, TGF-alpha, HRG-alpha, HRG-beta1, and HRG-beta3 in 100 frozen breast carcinoma materials was immunohistochemically studied. Among these tumors, 67% were positive for EGF, 53% for HB-EGF, 57% for TGF-alpha, 60% for HRG-alpha, 53% for HRG-beta1, and 63% for HRG-beta3 in the neoplastic epithelial cells. No significant associations between expression of the growth factors and clinicopathological features like tumor size, histologic grade, node status, ploidy, ER status, and c-erbB-4 expression were observed, with the exceptions that significant relations were present between EGF expression and tumor size (p = 0.01) and between HRG-beta3 expression and node status (p = 0.02). The expressions of these growth factors showed no association with cancer-specific survival by the Kaplan Meier analysis. 相似文献
100.
One of the most studied onco-gene families in breast tumors is the type 1 protein tyrosine kinase family, which consists of EGFR, c-erbB-2, c-erbB-3, and c-erbB-4. Overexpression of c-erbB-2 protein/mRNA in breast carcinomas is consistently associated with poor prognosis, while EGFR overexpression has been confirmed to have a synergistic clinical effect on the c-erbB-2 influence. The expression pattern of c-erbB-4 in breast carcinomas is special. Unlike other type 1 protein tyrosine kinases, expression of c-erbB-4 protein/mRNA is reduced in carcinomas compared with that in normal breast epithelia, and its expression has also been associated with a better clinical outcome, indicating the need for c-erbB-4 analysis when clinical therapeutic application of EGFR and c-erbB-2 anitbodies is considered. In addition, studies of the adaptor proteins in breast carcinomas are highly indicated in order to clarify the mechanisms behind the dysregulated expression of such receptors in breast carcinomas. 相似文献